Re: Add estimated hit ratio to Memoize in EXPLAIN to explain cost adjustment - Mailing list pgsql-hackers

From Robert Haas
Subject Re: Add estimated hit ratio to Memoize in EXPLAIN to explain cost adjustment
Date
Msg-id CA+TgmoZjVQf1-y2yj2OPWuL-eF=+UNv_vTUm_-98wg+Djj-vdA@mail.gmail.com
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In response to Re: Add estimated hit ratio to Memoize in EXPLAIN to explain cost adjustment  (David Rowley <dgrowleyml@gmail.com>)
Responses Re: Add estimated hit ratio to Memoize in EXPLAIN to explain cost adjustment
List pgsql-hackers
On Mon, Apr 14, 2025 at 8:23 PM David Rowley <dgrowleyml@gmail.com> wrote:
> Maybe we could compress the text output a bit with:
>
> "Estimates: capacity=N distinct keys=N hit ratio=N.N%"

Sure, that works for me.

> If we get it that compact, maybe lookups could fit in there too, i.e.:
>
> "Estimates: capacity=N distinct keys=N lookups=N hit ratio=N.N%"

Is lookups=N here the estimated number of lookups i.e. what we think
nloops will end up being?

--
Robert Haas
EDB: http://www.enterprisedb.com



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